Electric heater



n. 1. PATIERSON.

ELECTRIC HEATER.. APPLrATloN mio nov. 2,1, lszp Patented 0ct24,1922.

Patented Oct. 24, 1922.

PATENT` OFFICE.

RALPH J'. PATTERSON, OF BOSTON, MASSACHUSETTS.

ELECTRIC HEATER.

Application led November 21, 1921. Serial No. 516,732.y

T all whom t may concern-f Be it known that I, RALPH J. PATTERSON,

a citizen of the United States, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Electric Heaters, of which the following is a specification.

This invention relates to electric heaters, and more particularly to electric water heaters of the immersion type.

An object of the invention is 'to provide means for automatically opening the circuit when the heating units or the heating receptacle become overheated due to failure of the water supply or other causes, thus preventing the receptacle and heating unit from being damaged by excessive heat.

In the present invention, I employ a material that is of sufficient conductivity to convey the current` from the lead wires to the heating units, but which will melt at a much lower temperature than the material of which the heating elements and the body of the heater are made, whereby the connections will be broken if the water supply is shut off from any cause or excessive. overheating results from any other cause.

A clip of tin, zinc, or an alloy which will melt at a temperature below the temperature necessary to burn out the heating units is secured to the end of each lead wire and in turn connected to the heating units, whereby it is necessary for the current to pass through the clips before reaching the heater. 35 If the supply of water fails or the device becomes overheated from any other cause, the heat generated melts the clips and breaks the circuit.

In the accompan ing drawings, I have shown several embo iments of the invention. In this showing: v

Figure l is a side elevation, parts being shown in section, of a heater employing a plurality of heating units,

Figure 2 is a plan view thereof,

Figure 3 is a plan view of the heater employing a single heating element,

igure 4 is a side elevation of a slightly modified form of the invention showing the clip applied to the water outlet pipe,

Figure 5 is a plan view of the form shown in Figure 4 of the drawings, with the cover removed,

Figure 6 is a detail view of the form of the invention shown in Figures 1. and Q, and,

Figure 7 is a detail view of a lead wire showing thel control member in the form of a lug on the end of the wire.

Referring to Figures l, 2, and 6 of the drawings, the reference numeral l designates a suitable receptacle having openings at the top and bottom adapted to he connected to pipes 2, in a water supply line to permit the water to pass through the receptacle. A plurality of heating units 3 are arranged within the vessel or receptacle. These heating units are connected to an electric circuit by means of lead wires 4. A plurality of clips 5 of tin, zinc, or an alloy which is sufficiently conductive to convey the current from the 'lead wires to the heating units, but which will melt at a low temperature,

yare connected to binding posts 6, formed on the heating units. As shown, the upper ends of the binding posts'may be threaded, as at 7, and these threaded ends are adapted to be passed through openings 8, formed adjacent the ends of the clips and nuts 9 arranged thereon. Intermediate its ends, each clip is provided with an opening 10, adapted to receive .a screw ll. 'The end of the wire is coiled, as at l2, and is adapted to be arranged over the screw 1l, a nut 13 being placed on the end of the screw to hold the wire in position. As shown, the lead wires 4 are connected to a adjacent each other and a pair ofauxiliary lead wires 14 are provided to deliver' current tothe clips arranged diametrically opposite the clips to which the main lead wires are connected. By referring to Figure 2 Yof the drawings, it will be seen that the current flows in one of the lead wires and passes to` two of the heaters through the first clip, a portion of the current passing through the auxiliary lead wire 14 to the opposite clip. After passing through the heaters, the current passes through the other clips to the other lead wire.

In the form of the invention shown in Figure 3 of the drawings, a single heating unit is employed, having a binding post 15 to which one of the lead wires is directly connected. A clip 16 formed of materia] similar to that employed in the construction of clip 5 is provided, having an opening ad jacent each end. One of these openings is pair of clips arranged arranged over the binding post 17 of the heater, and the other lead Wire is connected to the opposite end et the Clip by means oi' a scren7 18.

In the term oit the invention shown in Figure 7 of the drawings, a lug 20 is pror vided on the end of the lead Wire, the lug being of the usual construction and having a sleeve 2l by means of Which it is secured to the end of the lead Wire. The tree end oft the lug is provided With an opening 22, adapted to be arranged over the binding post ol? the heater. In the use of the 'torni ol. the intention 4shown in Figure 7 of the drawings, the clip 2() may be arranged on either or both ofthe lead Wires. r

lfn the 'iorin ot theV invention shown in Figures Il; and 5 of the drawings, the clip instead ot being arranged directly over the heating units7 is mounted in a litting which may be secured to the het Water outlet pipe. The position of the litting is illustrated in Figure l `oi! the drawings arranged over the hot Water pipev directly above the heater. is shown, a sleeve 23 is adapted to be ar ranged over the het Water pipe andthis sleeve is provided ivith a boss or enlargement 24k, forming the base of the fitting. A suitable insulating base 25 is arranged xvithinfthe-titting and a pair ci conductor members 2G are supported on this base and spaced Afrom each other. The lead Wires 4i are connected to these two strips, the ends ot the Wires being secured to the conductor members by means oi screws 27. The conductor members are further `Connected to each other by a Wire or clip 28 extending across the fitting and connected to each oi; the conductor mem bers, asiat 29. The fitting may be provided. with a suitable cover 30, having an opening therein tor the reception of a'plug 3l of insulating material. The lead Wires pass through this plug'.

The operation 4of the device will `be apparent. The current normally passes 'through the Clips to the heating units, but if the heating units become overheated, due to any cause. su'eh as the shutting oli of the Water supply, heat is conveyed by radiation and conduction to the clips which are termed of a material which will melt before the overheating reaches laclanger point. When the' clips melt, the circuit is, olf course, broken and every danger ot overheating is elimi nated.

In the form of the invention shown in Figures d and 5 of the drawings, the heat radiated from the Water when the lWater is heated to an excessive temperature, or radiated through the outlet pipe 2, raises 'the temperature of the member 28 to the melting point and thus breaks the circuit.

lt is to be understood that the forms ot my invention herewith shown and described are to be taken as preferred. examples ot the same, and that various changes in the shape, size. and arrangement ot Vparts may be resorted to Without departing irom the spirit. oi the invention or the scope oft the suboined claims.

l. claim:

l. in electric heater comprising a plurality of heating units, each of said units being provided with a pair of binding posts, fusible clips connecting the adjacent binding posts ot said units, and means :for connecting a lead Wire to eaeh of said clips intermediate its ends.

in electric heater comprising a pluv rality oit heating units, each ot said units being providerfl with a pair of binding posts, clips connecting the adjacent binding posts otI said units, lead. Wiresl connected to alternate clips whereby current will l'loW through one set et clips to the heating units thence through the other set of clips to the other lead Wire. v

3. .in electric heater comprising a plurality ot heating units, eaoh of said units being provided with a pair of binding posts, (.-lips'connecting the adjacent binding posts oi said units7 said clips being 'formed of a material having a low melting point, lead Wires lconnected to alternate Clips whereby Current Will tlmv through one of said clips to the heating units thence throughthe other set ot' clips to the other lead Wire.

ln testimony 'whereof l my signature in presence or two Witnesses.

'tAlQPll il'. PATTERSN.

lllitnesses M. E. CLARK, A.VL. SMITH. 

